Can a streamlined ship go underwater ?

[phavoc]

Here's the problem. Starships that have no inherent ability to counteract gravity would never be able to land and operate near cities - especially the futurisitic cities with 110+ floor buildings adjacent to (and surrounding) a starport.

They can: the Starship Operators Manual, Vol. 1 explains this in detail. I believe it is canon. Explicitly ships do not have anti-gravity drive in MT.

That is a reasonable assumption to make.

I have noticed that many want to make that assumption, and you can of course do as you wish in your game. It is not necessary for Traveller to work.

I believe MgT2 avoids these details to allow players to play as they wish which is why I noted that it is you can assume it or not:

You can of course assume whatever you want in YTU; I don't assume that spacecraft automatically have anti-grav drives unless they install a specific anti-grav drive.

Anti-gravity does in fact equal contra-gravity. How? By the definition of the words.

They are two different technical systems with different functional details, even if the names are similar.

None of this is made any easier with the jumble of rule sets and the inconsistency across them. Though I suppose it does make for some interesting forum fodder.

All of this is clearly defined in editions that care about detail, e.g. MT, TNE, and T5.

I believe we can settle the argument about whether or not Traveller ships have antigrav/contragrav lifters (you may dispute the definitions further but that's for another thread). You mad a statement about assumptions and a "YTU". I recently received my copy of Flatlined. Since this is an official MGT publication, the statement given in it makes it canon. On pg 8 there is a description of a craft, "the pilot managed to use residual energy in the ships lifters..." Checking the ship stats there is no mention of any special function or feature other than the standard M-drive that is on every ship profile.

So it would seem that without another mention of ships that specifically preclude the installation of a antigrav/contragrav lifters, that the default would be ships capable of landing on a world do, in fact, have them.

I am still interested in how you define antigrav and contragrav to be different systems. Which rule set are you pulling this from?

[Condottiere]

My feeling is that we've accepted the thrust vectoring aspect of gravitational based drives.

But in the hovering aspect, it would be a case of diminishing returns, in comparison with actual anti-gravity lifters.

[AnotherDilbert]

I am still interested in how you define antigrav and contragrav to be different systems. Which rule set are you pulling this from?

Anti-grav is defined in MT and T5, used in CT and MgT.
Contra-grav is defined in TNE.

As already stated in this thread: Anti-grav drives provides lift and propulsion (like a helicopter), contra-grav drives negates most gravitational pull but does not provide thrust for propulsion (like a hot-air ballon).

On pg 8 there is a description of a craft, "the pilot managed to use residual energy in the ships lifters..."

We can trade quotes all day long, it is not clearly defined in MgT.

This hints that spacecraft does not have anti-grav drives as standard.

A streamlined ship is designed to enter a planetary atmosphere, and can function like a conventional aircraft.
...
Partial streamlining allows a ship to skim gas giants and enter Atmosphere codes of 3 or less, acting in the same way as streamlined ships. In other atmospheres, the ship will be ponderous and unresponsive, reliant on its thrusters to keep it aloft.

I would rate the core rules above a fluff statement in an adventure, but that is just me, you can assume anything you like...

[phavoc]

Well, we had this same conversation 2 yrs ago (viewtopic.php?f=89&t=119461) and it wasn't settled then. The odds of it settling now aren't any better with age. We can call the devices whatever (contragrav, antigrav, lifters, oatmeal cookies, etc). The idea doesn't change, just the definitions between the many settings and publishers of Traveller.

Plus I don't think anyone is going to budge, so there's not point in continuing the thread.

[phavoc]

As an aside, for those of us who read Space Vikings (and for whom the Sword Worlders are named), I found an interesting blog post talking about size comparisons - the Space Viking ships of old were MASSIVE when compared to most Traveller starships. The Nemesis would be about a 2 million DT ship in Travller. There are some interesting size comparisons at the blog for those who like that sort of thing - http://www.enderra.com/2011/10/14/starsship-sizes/

[Condottiere]

Machinery may operate under the same principles, but some may be more efficient or specialized to function in a specific way.